Compounds having a zinc-binding moiety, such as, for example, a hydroxamic acid group, can inhibit histone deacetylase. Histone deacetylase inhibition can repress gene expression, including expression of genes related to tumor suppression. Inhibition of histone deacetylase can lead to the histone deacetylase-mediated transcriptional repression of tumor suppressor genes. For example, inhibition of histone deacetylase can provide an alternate route for treating cancer, hematological disorders, such as hematopoiesis, and genetic related metabolic disorders, such as, cystic fibrosis and adrenoleukodystrophy.
One aspect of the invention relates to HDAC inhibitors. Methods of sensitizing a cancer cell to the cytotoxic effects of radiotherapy are also provided. The invention also provides methods for treating cancer and methods for treating neurological diseases. Additionally, the invention further provides pharmaceutical compositions comprising an HDAC inhibitor of the invention, and kits comprising a container containing an HDAC inhibitor of the invention.
Histone deacetylase is a metallo-enzyme with zinc at the active site. Compounds having a zinc-binding moiety, for example, an alpha-chalcogenmethylcarbonyl group, such as an alpha-ketothio group, can inhibit histone deacetylase. Histone deacetylase inhibition can repress gene expression, including expression of genes related to tumor suppression. Accordingly, inhibition of histone deacetylase can provide an alternate route for treating cancer, hematological disorders, e.g., hemoglobinopathies, autosomal dominant disorders, e.g. spinal muscular atrophy and Huntington's disease, genetic related metabolic disorders, e.g., cystic fibrosis and adrenoleukodystrophy, or for stimulating hematopoietic cells ex vivo.
The present invention relates to prolonged-release oral dosage forms of 4-phenylbutyric acid salts, such as sodium 4-phenylbutyrate. The prolonged release oral dosage forms are preferably tablets. The prolonged release is achieved by formulating 4-phenylbutyric acid with a delaying matrix material, such as hydroxypropylmethyl cellulose. The prolonged release oral dosage forms of the present invention may be administered once or twice a day to a patient suffering from a disease such as cancer or a urea cycle disorder.
The present invention provides methods of selectively inducing terminal differentiation, cell growth arrest and/or apoptosis of neoplastic cells, and/or inhibiting histone deacetylase (HDAC) by administration of pharmaceutical compositions comprising potent HDAC inhibitors. The oral bioavailability of the active compounds in the pharmaceutical compositions of the present invention is surprisingly high. Moreover, the pharmaceutical compositions unexpectedly give rise to high, therapeutically effective blood levels of the active compounds over an extended period of time. The present invention further provides a safe, daily dosing regimen of these pharmaceutical compositions, which is easy to follow, and which results in a therapeutically effective amount of the HDAC inhibitors in vivo. The present invention also provides a novel Form I polymorph of SAHA, characterized by a unique X-ray diffraction pattern and Differential Scanning Calorimetry profile, as well a unique crystalline structure.
